Conductive structure, multilayer ceramic capacitor and manufacturing method of multilayer ceramic capacitor

Abstract

The invention relates to the technical field of capacitors, in particular to a conductive structure, a multi-layer ceramic capacitor and a manufacturing method of the multi-layer ceramic capacitor, the conductive structure comprises a ceramic body, an auxiliary electrode and an outer electrode, and the ceramic body is provided with a plurality of inner electrodes which are arranged at intervals along a first direction; each inner electrode is exposed to the first end face or the second end face of the ceramic body, and each inner electrode is exposed to the third end face and / or the fourth end face of the ceramic body; auxiliary electrodes are arranged on the third end face with the exposed inner electrodes and / or the fourth end face with the exposed inner electrodes, and the auxiliary electrodes are electrically connected with the inner electrodes; the inner electrode is exposed to the first end face or the second end face and is also exposed to the third end face and / or the fourth end face, and the inner electrode exposed to the third end face and the fourth end face is electrically connected with the outer electrode through the auxiliary electrode, so that the contact area of the inner electrode and the outer electrode is increased, and the auxiliary electrode and the ceramic body can be processed in parallel; and large-batch processing of the multilayer ceramic capacitor is facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of capacitors, and in particular to a conductive structure, a multilayer ceramic capacitor and a method for manufacturing the multilayer ceramic capacitor. Background Art

[0002] Multilayer ceramic capacitors are composed of a ceramic body and an external electrode, wherein the ceramic body includes a ceramic dielectric layer and an internal electrode. As the capacity of multilayer ceramic capacitors increases, the thickness of the internal electrode of the multilayer ceramic capacitor is greatly reduced, and the area of ​​the internal electrode exposed on the surface of the multilayer ceramic capacitor is reduced accordingly, thereby reducing the contact area between the internal electrode and the external electrode, making it easy to have poor contact, resulting in a decrease in the capacitance of the multilayer ceramic capacitor.

[0003] The Chinese invention patent with the authorization announcement number CN115274300B discloses a multilayer ceramic capacitor, which is provided with a conductive hole extending along the stacking direction of the inner electrode in the middle of the ceramic body, and then a perforated electrode is provided in the conductive hole, and the perforated electrode is used to connect the inner electrodes in parallel, thereby improving the conductivity of the inner electrode and the outer electrode. However, when using this conductive structure, it is necessary to first punch holes in the inner electrode, fill the conductive material after stacking the inner electrode, and sinter it, or first stack the inner electrode, then punch holes in the stacked inner electrode, and finally fill the conductive material and sinter it. The operations of drilling the conductive hole, filling the conductive material into the conductive hole, and sintering are all relatively complicated, and the above steps need to be performed in sequence, which is time-consuming and not conducive to the mass production of multilayer ceramic capacitors. Summary of the invention

[0004] The technical problem to be solved by the present invention is: the conductive structure of the existing multilayer ceramic capacitor improves the contact area between the inner electrode and the outer electrode by processing a conductive hole in the inner electrode, filling the conductive hole with a conductive material, and then sintering the conductive material. The construction process of the conductive structure is complicated and each process needs to be performed in sequence, resulting in a long processing period for the conductive structure, which is not conducive to mass processing of multilayer ceramic capacitors.

[0005] In order to solve the above technical problems, the object of the present invention is to provide a conductive structure, which is used for a multilayer ceramic capacitor, wherein the conductive structure has a first direction Z, a second direction X and a third direction Y that intersect each other, and the conductive structure for the multilayer ceramic capacitor includes:

[0006] A ceramic body, wherein the ceramic body has a plurality of internal electrodes arranged at intervals along the first direction Z, wherein two end faces of the ceramic body arranged opposite to each other along the second direction X are respectively a first end face and a second end face, and two end faces of the ceramic body arranged opposite to each other along the third direction Y are respectively a third end face and a fourth end face; each of the internal electrodes is exposed to the first end face or the second end face, and each of the internal electrodes is exposed to the third end face and / or the fourth end face;

[0007] an auxiliary electrode, the auxiliary electrode being attached to a position of the third end surface where the inner electrode is exposed and / or a position of the fourth end surface where the inner electrode is exposed, and the auxiliary electrode being electrically connected to each of the inner electrodes;

[0008] An external electrode is disposed at a position of the first end surface where the internal electrode is exposed or at a position of the second end surface where the internal electrode is exposed, and the external electrode is electrically connected to the auxiliary electrode and each of the internal electrodes.

[0009] As a preferred embodiment, the conductive structure for the multilayer ceramic capacitor also includes a protective sheet, which is bonded to the position of the third end surface where the inner electrode is exposed and / or the position of the fourth end surface where the inner electrode is exposed, and the auxiliary electrode is attached to the bonding end of the protective sheet.

[0010] A multilayer ceramic capacitor, the multilayer ceramic capacitor adopts the above-mentioned conductive structure for a multilayer ceramic capacitor; the multilayer ceramic capacitor comprises a ceramic body, a first auxiliary electrode, a second auxiliary electrode, a first external electrode and a second external electrode:

[0011] The ceramic body has a plurality of first internal electrodes and a plurality of second internal electrodes arranged alternately and spaced along a first direction Z; each of the first internal electrodes is arranged spaced from the second end surface of the ceramic body, and each of the second internal electrodes is arranged spaced from the first end surface of the ceramic body;

[0012] Each of the first internal electrodes is exposed to the first end surface of the ceramic body, and is exposed to the third end surface and / or the fourth end surface of the ceramic body; the first auxiliary electrode is provided at the position of the third end surface where the first internal electrode is exposed and / or at the position of the fourth end surface where the first internal electrode is exposed, and the first auxiliary electrode is electrically connected to each of the first internal electrodes; the first external electrode is provided at the first end surface, and the first external electrode is electrically connected to the first auxiliary electrode and each of the first internal electrodes exposed to the first end surface;

[0013] Each of the second inner electrodes is exposed to the second end surface, and is exposed to the third end surface and / or the fourth end surface; the third end surface and / or the fourth end surface is provided with the second auxiliary electrode, and the second auxiliary electrode is electrically connected to the second inner electrode exposed to the third end surface and / or the fourth end surface; the second outer electrode is arranged on the second end surface, and the second outer electrode is electrically connected to the second auxiliary electrode and each of the second inner electrodes exposed to the second end surface.

[0014] As a preferred solution, the first inner electrode is exposed to the third end surface and the fourth end surface, the third end surface and the fourth end surface are both provided with the first auxiliary electrodes, each of the first auxiliary electrodes is arranged at an interval with each of the second inner electrodes, and an end of each of the first auxiliary electrodes extends to the first end surface;

[0015] The second inner electrode is exposed to the third end surface and the fourth end surface, the third end surface and the fourth end surface are both provided with the second auxiliary electrodes, each of the second auxiliary electrodes is arranged at an interval with each of the first inner electrodes, and the end of each of the second auxiliary electrodes extends to the second end surface.

[0016] As a preferred solution, the multilayer ceramic capacitor includes a first protection sheet attached to the third end surface and a second protection sheet attached to the fourth end surface;

[0017] The first auxiliary electrode and the second auxiliary electrode located at the third end surface are attached to the bonding end of the first protective sheet by means of additive manufacturing; the first auxiliary electrode and the second auxiliary electrode located at the fourth end surface are attached to the bonding end of the second protective sheet by means of additive manufacturing.

[0018] As a preferred solution, the first internal electrode is exposed to the third end surface, and the first internal electrode is spaced apart from the fourth end surface, and the first auxiliary electrode is arranged on the third end surface;

[0019] The second inner electrode is exposed to the fourth end surface, and the second inner electrode is spaced apart from the third end surface, and the second auxiliary electrode is disposed on the fourth end surface.

[0020] As a preferred solution, the multilayer ceramic capacitor includes a third protection sheet attached to the third end surface and a fourth protection sheet attached to the fourth end surface;

[0021] The first auxiliary electrode is a conductive layer attached to the bonding end of the third protective sheet by an additive method, and the second auxiliary electrode is a conductive layer attached to the bonding end of the fourth protective sheet by an additive method.

[0022] As a preferred solution, the thickness of each of the first internal electrodes and the thickness of each of the second internal electrodes are both greater than or equal to 0.5 μm and less than or equal to 1 μm.

[0023] As a preferred solution, the thickness of the first auxiliary electrode and the second auxiliary electrode are both greater than or equal to 0.5 μm and less than or equal to 3 μm.

[0024] A method for manufacturing the above-mentioned multilayer ceramic capacitor comprises the following steps:

[0025] Step S1, preparing a primary ceramic mother bar and a protection bar, wherein the primary ceramic mother bar is formed with a plurality of ceramic body units sequentially arranged along a first direction X, and the protection bar is formed with a plurality of protection sheet units sequentially arranged along the first direction X;

[0026] Step S2, pressing the protection strip on the third end face and the fourth end face of the primary ceramic mother bar to form a final ceramic mother bar;

[0027] Step S3, dividing the final ceramic body mother bar into a plurality of green ceramic bodies along the first direction X;

[0028] Step S4, sintering the green ceramic body into a finished ceramic body;

[0029] Step S5, processing a first external electrode and a second external electrode on the first end surface and the second end surface of the finished ceramic body.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The conductive structure for a multilayer ceramic capacitor of the present invention comprises a ceramic body, an auxiliary electrode and an external electrode, wherein the ceramic body has a plurality of internal electrodes arranged at intervals along a first direction, wherein two end faces of the ceramic body arranged opposite to each other along a second direction are respectively a first end face and a second end face, and two end faces arranged opposite to each other along a third direction are respectively a third end face and a fourth end face; each internal electrode is exposed to the first end face or the second end face, and each internal electrode is exposed to the third end face and / or the fourth end face; the third end face where the internal electrode is exposed and / or the fourth end face where the internal electrode is exposed are provided with an auxiliary electrode, and the auxiliary electrode is connected to each internal electrode The first end face where the inner electrode is exposed or the second end face where the inner electrode is exposed is provided with an external electrode outside, the external electrode is electrically connected to the auxiliary electrode and each inner electrode, the inner electrode is exposed to the third end face and / or the fourth end face in addition to the first end face or the second end face, the inner electrode exposed outside the third end face and the fourth end face is electrically connected to the external electrode through the auxiliary electrode, the contact area between the inner electrode and the external electrode is increased, poor contact between the inner electrode and the external electrode is avoided, and the auxiliary electrode and the ceramic body can be processed in parallel, shortening the processing period of the conductive structure, and facilitating mass processing of multilayer ceramic capacitors. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A schematic structural diagram of a conductive structure for a multilayer ceramic capacitor of the present invention;

[0033] Figure 2 is an axonometric view of a multilayer ceramic capacitor of the present invention;

[0034] Figure 3 An isometric view of a ceramic body in a first embodiment of a multilayer ceramic capacitor of the present invention when the first auxiliary electrode and the second auxiliary electrode are not connected;

[0035] Figure 4 An isometric view of a ceramic body after a first auxiliary electrode and a second auxiliary electrode are provided in a first embodiment of the multilayer ceramic capacitor of the present invention;

[0036] Figure 5 It is an isometric view of the ceramic body after the first protection sheet and the second protection sheet are connected in the first embodiment of the multilayer ceramic capacitor of the present invention;

[0037] Figure 6 A cross-sectional view of the multilayer ceramic capacitor in the first embodiment of the present invention along the X direction;

[0038] Figure 7 for Figure 6 Middle AA section view;

[0039] Figure 8 for Figure 6 Middle BB section view;

[0040] Fig. 9 An isometric view of a second embodiment of a multilayer ceramic capacitor of the present invention, wherein the ceramic body is not connected to the first auxiliary electrode;

[0041] Fig.10 An isometric view of a ceramic body after connecting a first auxiliary electrode in a second embodiment of a multilayer ceramic capacitor of the present invention;

[0042] Fig.11 A cross-sectional view of the multilayer ceramic capacitor in the X direction in the second embodiment of the multilayer ceramic capacitor of the present invention;

[0043] Fig.12 for Fig.11 CC section view;

[0044] Fig.13 for Fig.11 DD section view;

[0045] Fig.14 A schematic diagram of processing the structure of the inner electrode film layer area on the ceramic film, and the subsequent first cutting path and second cutting path;

[0046] Fig.15 A schematic diagram of a structure for cutting a ceramic mother board into a plurality of primary ceramic mother strips;

[0047] Fig.16 This is an exploded view of the final ceramic body mother bar;

[0048] Fig.17 It is a schematic diagram of the structure of the final ceramic body mother bar;

[0049] Fig.18 A schematic diagram of the structure of cutting a final ceramic body mother bar into a green ceramic body;

[0050] In the figure, Z, the first direction, X, the second direction, Y, the third direction, 1, ceramic body, 11, the first end face, 12, the second end face, 13, the third end face, 14, the fourth end face, 2, the inner electrode, 21, the first inner electrode, 22, the second inner electrode, 3, the auxiliary electrode, 31, the first auxiliary electrode, 32, the second auxiliary electrode, 4, the outer electrode, 41, the first outer electrode, 42, the second outer electrode, 5, the protective sheet, 51, the first protective sheet, 52, the second protective sheet, 53, the third protective sheet, 54, the fourth protective sheet, 100, the ceramic film, 101, the inner electrode film layer area, 103, the primary ceramic body mother bar, 1031, the ceramic body unit, 104, the final ceramic body mother bar, 200, the protective strip, 201, the protective sheet unit, 300, the auxiliary electrode area, 400, the raw ceramic body, L1, the first cutting path, L2, the second cutting path. DETAILED DESCRIPTION

[0051] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0052] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "top", "bottom", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. It should be understood that the terms "first", "second", etc. are used in the present invention to describe various information, but such information should not be limited to these terms, which are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present invention, the "first" information may also be referred to as the "second" information, and similarly, the "second" information may also be referred to as the "first" information.

[0053] Embodiment 1

[0054] like Figure 1As shown, a preferred embodiment of the conductive structure for a multilayer ceramic capacitor of the present invention, the conductive structure for a multilayer ceramic capacitor has a first direction Z, a second direction X and a third direction Y intersecting in pairs, the conductive structure for a multilayer ceramic capacitor comprises a ceramic body 1, an auxiliary electrode 3 and an external electrode 4, the ceramic body 1 has a plurality of internal electrodes 2 arranged at intervals along the first direction Z, and it is defined that two end faces of the ceramic body 1 arranged opposite to each other along the second direction X are respectively a first end face 11 and a second end face 12, and two end faces arranged opposite to each other along the third direction Y are respectively a third end face 13 and a third end face 14. Four end surfaces 14; each internal electrode 2 is exposed at the first end surface 11 or the second end surface 12, and each internal electrode 2 is exposed at the third end surface 13 and / or the fourth end surface 14; an auxiliary electrode 3 is attached at the position where the internal electrode 2 is exposed on the third end surface 13 and / or the position where the internal electrode 2 is exposed on the fourth end surface 14, and the auxiliary electrode 3 is electrically connected to each internal electrode 2; an external electrode 4 is provided at the position where the internal electrode 2 is exposed on the first end surface 11 or the position where the internal electrode 2 is exposed on the second end surface 12, and the external electrode 4 is electrically connected to the auxiliary electrode 3 and each internal electrode 2. Among them, in addition to being exposed to the first end face 11 or the second end face 12, the inner electrode 2 is also exposed to the third end face 13 and / or the fourth end face 14. The inner electrode 2 exposed outside the third end face 13 and the fourth end face 14 is electrically connected to the outer electrode 4 through the auxiliary electrode 3, thereby increasing the contact area between the inner electrode 2 and the outer electrode 4 and avoiding poor contact between the inner electrode 2 and the outer electrode 4. Moreover, the auxiliary electrode 3 and the ceramic body 1 can be processed in parallel, shortening the processing period of the conductive structure and facilitating mass processing of multilayer ceramic capacitors.

[0055] Specifically, the ceramic body 1 in this embodiment is a rectangular parallelepiped, the thickness direction of the ceramic body 1 is arranged along the first direction Z, the length direction of the ceramic body 1 is arranged along the second direction X, the width direction of the ceramic body 1 is arranged along the third direction Y, and each inner electrode 2 is arranged in parallel and spaced apart along the first direction Z. The shape of each inner electrode 2 is a square thin sheet extending parallel to the XY plane, one end of each inner electrode 2 extends to the first end face 11 and is exposed to the first end face 11, one end of each inner electrode 2 close to the third end face 13 extends to the third end face 13 and is exposed to the third end face 13, one end of each inner electrode 2 close to the fourth end face 14 extends to the fourth end face 14 and is exposed to the fourth end face 14, and one end of each inner electrode 2 close to the second end face 12 is not exposed from the second end face 12. Auxiliary electrodes 3 are provided on both the third end face 13 and the fourth end face 14. The auxiliary electrodes 3 located at the third end face 13 cover the inner electrode 2 exposed to the third end face 13, and the auxiliary electrodes 3 located at the fourth end face 14 cover the inner electrode 2 exposed to the fourth end face 14. The ends of the two auxiliary electrodes 3 facing the first end face 11 are flush with the first end face 11, and the outer electrode 4 abuts against the ends of the two auxiliary electrodes 3 and the first end face 11, so that the outer electrode 4 directly contacts and conducts with the ends of each inner electrode 2 exposed to the first end face 11, and the outer electrode 4 contacts and conducts with the ends of each auxiliary electrode 3. In other embodiments of the present invention, each inner electrode 2 is exposed to one of the third end face 13 and the fourth end face 14 in addition to being exposed to the first end face 11, and the auxiliary electrodes 3 are provided accordingly.

[0056] In this embodiment, the continuity of the auxiliary electrode 3 is better than that of the inner electrode 2, so that the auxiliary electrode 3 forms good contact with the inner electrode 2 and the outer electrode 4. The material of the auxiliary electrode 3 is nickel.

[0057] The conductive structure for the multilayer ceramic capacitor further includes a protective sheet 5, which is bonded to the third end face 13 where the inner electrode 2 is exposed and / or the fourth end face 14 where the inner electrode 2 is exposed, and the auxiliary electrode 3 is attached to the bonded end of the protective sheet 5. Specifically, the protective sheet 5 is a rectangular thin sheet made of ceramic material, and the four sides of the protective sheet 5 arranged at the third end face 13 are respectively flush with the four sides of the third end face 13, and the four sides of the protective sheet 5 arranged at the fourth end face 14 are respectively flush with the four sides of the fourth end face 14, so as to ensure that the protective sheet 5 completely covers the third end face 13 and the fourth end face 14. The protective sheet 5 covers the third end face 13 and the fourth end face 14, plays a role in moisture-proof and mechanical damage-proof, and can improve the reliability of the multilayer ceramic capacitor.

[0058] When the thickness of the protective sheet 5 is too small, the moisture-proof and mechanical damage-proof effects of the protective sheet 5 will be weakened; when the thickness of the protective sheet 5 is too large, it is not conducive to improving the capacitance of the multilayer ceramic capacitor. In this embodiment, the thickness of the protective sheet 5 is greater than or equal to 50μm and less than or equal to 200μm, which not only ensures the moisture-proof and mechanical damage-proof effects of the protective sheet 5, but also ensures the capacitance of the multilayer ceramic capacitor.

[0059] Embodiment 2

[0060] A first embodiment of the multilayer ceramic capacitor of the present invention adopts the above-mentioned conductive structure for multilayer ceramic capacitors, such as Figures 2 to 8 As shown, the multilayer ceramic capacitor includes a ceramic body 1, a first auxiliary electrode 31, a second auxiliary electrode 32, a first external electrode 41 and a second external electrode 42:

[0061] The ceramic body 1 has a plurality of first internal electrodes 21 and a plurality of second internal electrodes 22 arranged alternately and spaced along a first direction Z; each first internal electrode 21 is spaced from the second end surface 12 of the ceramic body 1, and each second internal electrode 22 is spaced from the first end surface 11 of the ceramic body 1;

[0062] The arrangement of each first inner electrode 21, the first auxiliary electrode 31 and the first outer electrode 41 adopts the above-mentioned conductive structure for a multilayer ceramic capacitor; specifically, each first inner electrode 21 is exposed to the first end surface 11 of the ceramic body 1, and is exposed to the third end surface and the fourth end surface 14 of the ceramic body 1; the third end surface 13 and the fourth end surface 14 are both provided with a first auxiliary electrode 31, and the first auxiliary electrode 31 is electrically connected to each first inner electrode 21; the first outer electrode 41 is arranged on the first end surface 11, and the first outer electrode 41 is electrically connected to the first auxiliary electrode 31 and each first inner electrode 21 exposed to the first end surface 11;

[0063] The arrangement of each second inner electrode 22, the second auxiliary electrode 32 and the second outer electrode 42 adopts the above-mentioned conductive structure for the multilayer ceramic capacitor; specifically, each second inner electrode 22 is exposed to the second end surface 12, and is exposed to the third end surface 13 and the fourth end surface 14; the third end surface 13 and the fourth end surface 14 are both provided with a second auxiliary electrode 32, and the second auxiliary electrode 32 is electrically connected to the second inner electrode 22; the second outer electrode 42 is arranged on the second end surface 12, and the second outer electrode 42 is electrically connected to the second auxiliary electrode 32 and each second inner electrode 22 exposed to the second end surface 12.

[0064] In this embodiment, Figure 3As shown, the first inner electrode 21 is exposed to the first end surface 11, the third end surface 13 and the fourth end surface 14, and is not exposed to the second end surface 12. The third end surface 13 and the fourth end surface 14 are both provided with a first auxiliary electrode 31, each first auxiliary electrode 31 is arranged at an interval with each second inner electrode 22, and an end portion of each first auxiliary electrode 31 extends to the first end surface 11; the second inner electrode 22 is exposed to the second end surface 12, the third end surface 13 and the fourth end surface 14, and is not exposed to the first end surface 11. The third end surface 13 and the fourth end surface 14 are both provided with a second auxiliary electrode 32, each second auxiliary electrode 32 is arranged at an interval with each first inner electrode 21, and an end portion of each second auxiliary electrode 32 extends to the second end surface 12.

[0065] Furthermore, the multilayer ceramic capacitor includes a first protective sheet 51 bonded to the third end face 13 and a second protective sheet 52 bonded to the fourth end face 14; the first auxiliary electrode 31 and the second auxiliary electrode 32 located at the third end face 13 are attached to the bonding end of the first protective sheet 51 by additive manufacturing; the first auxiliary electrode 31 and the second auxiliary electrode 32 located at the fourth end face 14 are attached to the bonding end of the second protective sheet 52 by additive manufacturing.

[0066] Specifically, the processing steps of the first protective sheet 51 and the second protective sheet 52 are as follows: first, ceramic powder, adhesive, and organic solvent are mixed to form a ceramic slurry, and the ceramic slurry is cast into a ceramic film. The material of the ceramic powder can be barium titanate, calcium zirconate, etc. The thickness of the ceramic film can be, for example, 1 μm to 20 μm. Then, multiple ceramic films are stacked and pressed to obtain the first protective sheet 51 and the second protective sheet 52, and then nickel metal slurry is printed on the bonding end surfaces of the first protective sheet 51 and the second protective sheet 52 and dried to form a first auxiliary electrode 31 attached to the first protective sheet 51 and a second auxiliary electrode 32 attached to the second protective sheet 52. The nickel metal slurry used in the first auxiliary electrode 31 and the second auxiliary electrode 32 can be the same as the nickel metal slurry used in the first internal electrode 21 and the second internal electrode 22, but different nickel metal slurries can also be used to make the continuity of the first auxiliary electrode 31 and the second auxiliary electrode 32 better than the continuity of the first internal electrode 21 and the second internal electrode 22. After the first protection sheet 51 and the second protection sheet 52 are processed, the first protection sheet 51 and the second protection sheet 52 can be respectively pressed onto the third end face 13 and the fourth end face 14 of the ceramic body 1. The processing of the first protection sheet 51 and the second protection sheet 52 can be carried out in parallel with the processing of the ceramic body 1, thereby shortening the overall processing cycle of the multilayer ceramic capacitor.

[0067] Embodiment 3

[0068] A second embodiment of the multilayer ceramic capacitor of the present invention is as follows Figure 2 , Figures 9 to 13As shown, the first inner electrode 21 is exposed to the first end face 11 and is also exposed to one of the third end face 13 and the fourth end face 14, and the second inner electrode 22 is exposed to the second end face 12 and is also exposed to the other of the third end face 13 and the fourth end face 14; in this embodiment, the first inner electrode 21 is exposed to the third end face 13 and is spaced apart from the fourth end face 14; the first auxiliary electrode 31 is arranged on the third end face 13; the second inner electrode 22 is exposed to the fourth end face 14 and is spaced apart from the third end face 13; the second auxiliary electrode 32 is arranged on the fourth end face 14.

[0069] When this arrangement is adopted, the first internal electrode 21 is only exposed to the first end face 11 and the third end face 13, and is not exposed to the fourth end face 14, and the second internal electrode 22 is not exposed to the third end face 13. Therefore, the third end face 13 only exposes the first internal electrode 21, so the third end face 13 can cover the first auxiliary electrode 31 except the edge position, thereby ensuring the contact area between the first auxiliary electrode 31 and the first internal electrode 21. Similarly, the fourth end face 14 only exposes the second internal electrode 22, and the fourth end face 14 can cover the second auxiliary electrode 32 except the edge position, thereby ensuring the contact area between the second auxiliary electrode 32 and the second internal electrode 22. Correspondingly, the multilayer ceramic capacitor includes a third protective sheet 53 attached to the third end face 13 and a fourth protective sheet 54 attached to the fourth end face 14; the first auxiliary electrode 31 is a conductive layer attached to the bonding end of the third protective sheet 53 by additive method, and the second auxiliary electrode 32 is a conductive layer attached to the bonding end of the fourth protective sheet 54 by additive method.

[0070] In the present embodiment, the materials of the first inner electrode 21 and the second inner electrode 22 are both nickel. When the thickness of the first inner electrode 21 and the second inner electrode 22 is too small, the continuity of the first inner electrode 21 and the second inner electrode 22 is poor, which is not conducive to improving the capacitance; when the thickness of the first inner electrode 21 and the second inner electrode 22 is too large, it is not conducive to reducing the thickness of the multilayer ceramic capacitor. In the present embodiment, the thickness of each first inner electrode 21 and the second inner electrode 22 is greater than or equal to 0.5μm and less than or equal to 1μm, so that a larger capacitance can be obtained in a smaller thickness.

[0071] When the thickness of the first auxiliary electrode 31 and the second auxiliary electrode 32 is too small, the continuity of the first auxiliary electrode 31 and the second auxiliary electrode 32 is poor and the connection area with the first external electrode 41 and the second external electrode 42 is small, which is not conducive to improving the conductivity; when the thickness of the first auxiliary electrode 31 and the second auxiliary electrode 32 is too large, a significant step will be generated at the edge of the first auxiliary electrode 31 and the second auxiliary electrode 32, which is not conducive to improving the bonding strength between the third protective sheet 53 and the fourth protective sheet 54 and the ceramic body 1. In this embodiment, the thickness of the first auxiliary electrode 31 and the second auxiliary electrode 32 is greater than or equal to 0.5μm and less than or equal to 3μm. The conductivity of the first auxiliary electrode 31 and the second auxiliary electrode 32 and the first external electrode 41 and the second external electrode 42 is guaranteed, and the bonding strength between the third protective sheet 53 and the fourth protective sheet 54 and the ceramic body 1 is guaranteed.

[0072] Embodiment 4

[0073] This embodiment is an embodiment of the method for manufacturing the multilayer ceramic capacitor of the above two embodiments. Figures 14 to 18 As shown, the manufacturing method of the multilayer ceramic capacitor of this embodiment can first parallelly process the ceramic body 1 and the protective sheet 5 with a conductive coating attached thereto serving as the auxiliary electrode 3, then press the protective sheet 5 with the ceramic body 1, and finally process the external electrode 4, which is convenient for batch processing.

[0074] Specifically, the method for manufacturing the multilayer ceramic capacitor of this embodiment includes the following steps:

[0075] Step S1, preparing a primary ceramic mother bar 103 and a protection bar 200, wherein the primary ceramic mother bar 103 is formed with a plurality of ceramic body units 1031 sequentially arranged along a first direction X, and the protection bar 200 is formed with a plurality of protection sheet units 201 sequentially arranged along the first direction X;

[0076] Step S2, pressing the protection strip 200 on the third end surface and the fourth end surface of the primary ceramic body mother bar 103 to form a final ceramic body mother bar 104;

[0077] Step S3, dividing the final ceramic body mother bar 104 into a plurality of green ceramic bodies 400 along the second direction X;

[0078] Step S4, sintering the green ceramic body 400 into a finished ceramic body;

[0079] Step S5, processing the first external electrode 41 and the second external electrode 42 on the first end surface and the second end surface of the finished ceramic body.

[0080] Wherein, in the step S1, preparing the primary ceramic mother bar comprises:

[0081] Step S11a, preparing the ceramic film 100; specifically, ceramic powder, adhesive, and organic solvent are mixed to form a ceramic slurry, and the ceramic slurry is cast into the ceramic film 100. The material of the ceramic powder can be barium titanate, calcium zirconate, etc. The thickness of the ceramic film 100 can be, for example, 1 μm to 20 μm.

[0082] Step S12a, processing the inner electrode film region 101 on the ceramic film 100; specifically, printing nickel metal paste on the ceramic film 100 and drying it to form the inner electrode film region 101. Fig.14 As shown, one internal electrode film layer region 101 can be cut into a plurality of internal electrodes 2 .

[0083] Step S13a, stacking a plurality of ceramic films 100 into a ceramic body motherboard; specifically, stacking a plurality of ceramic films 100 formed with an internal electrode film layer region 101 along a first direction Z, and covering the ceramic films 100 obtained in step S11a at both ends of the ceramic body motherboard along the first direction Z, to obtain a ceramic body motherboard. The purpose of covering the ceramic films 100 at both ends of the first direction Z is to cover the internal electrode film layer region 101 and protect the internal electrode film layer region 101 from moisture intrusion and mechanical damage. When stacking a plurality of ceramic films 100 formed with an internal electrode film layer region 101 along the first direction Z, adjacent ceramic films 100 are staggered in the second direction X.

[0084] Step S14a, cutting the ceramic mother board into a plurality of primary ceramic mother strips 103; specifically, Fig.15 As shown, the ceramic mother board is cut into a plurality of elongated primary ceramic mother strips 103 along the first cutting path L1 , the length direction of which is parallel to the second direction X. The cut surfaces in this step form the third end surface 13 and the fourth end surface 14 .

[0085] The step S1 of preparing the protective strip includes:

[0086] Step S12b, stack and compress the ceramic films 100 obtained in the multiple steps S11a to obtain the protection strip 200; print nickel metal paste on one end of the protection strip 200 and dry it, and the nickel metal paste layer forms the auxiliary electrode region 300. S12b can be performed in parallel with S12a.

[0087] In the step S2, when the protection strip 200 is pressed onto the third end face 13 and the fourth end face 14 of the primary ceramic body mother strip 103, as shown in FIG. Fig.16 As shown, during the pressing process, each ceramic body unit 1031 is bonded to each protection sheet unit 201 in a one-to-one correspondence. Fig.16The dotted line in the figure represents the second cutting path L2. The area between two adjacent second cutting paths L2 on the primary ceramic body mother bar 103 is a ceramic body unit 1031. The area between two adjacent second cutting paths L2 on the protection bar 200 is a protection sheet unit 201. The auxiliary electrode regions 300 are arranged at intervals on the bonding surface of the protection bar 200 along the second direction X. Each second cutting path L2 is located at the center of each auxiliary electrode region 300. In step S3, the final ceramic body mother bar 104 is cut along each second cutting path L2.

[0088] In step S3 , the cut green ceramic body 400 is in the shape of a cuboid, and the cut surface in this step forms the first end face 11 and the second end face 12 of the ceramic body 1 .

[0089] In the step S4, the green ceramic body 400 is debinded and sintered.

[0090] In the step S5, the first external electrode 41 and the second external electrode 42 are coated on the first end surface 11 and the second end surface 12 of the finished ceramic body to obtain a multilayer ceramic capacitor.

[0091] In summary, in the conductive structure for multilayer ceramic capacitors of the present invention, the inner electrode 2 exposed outside the third end face 13 and the fourth end face 14 is electrically connected to the outer electrode 4 through the auxiliary electrode 3, which increases the contact area between the inner electrode 2 and the outer electrode 4, avoids the poor contact between the inner electrode 2 and the outer electrode 4, and the auxiliary electrode 3 and the ceramic body 1 can be processed in parallel, shortening the processing period of the conductive structure, and facilitating the mass processing of multilayer ceramic capacitors. The multilayer ceramic capacitors of the present invention use the above-mentioned conductive structure for multilayer ceramic capacitors at both ends of the multilayer ceramic capacitors, ensuring the conductivity and capacitance of the multilayer ceramic capacitors. The manufacturing method of the multilayer ceramic capacitors of the present invention has high processing efficiency and is convenient for mass processing of multilayer ceramic capacitors.

[0092] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A conductive structure for a multilayer ceramic capacitor, having a first direction (Z), a second direction (X) and a third direction (Y) intersecting each other, characterized in that: include: A ceramic body (1), wherein the ceramic body (1) has a plurality of internal electrodes (2) arranged at intervals along the first direction (Z), wherein two end faces of the ceramic body (1) arranged opposite to each other along the second direction (X) are respectively a first end face (11) and a second end face (12), and two end faces arranged opposite to each other along the third direction (Y) are respectively a third end face (13) and a fourth end face (14); each of the internal electrodes (2) is exposed to the first end face (11) or the second end face (12), and each of the internal electrodes (2) is exposed to the third end face (13) and / or the fourth end face (14); an auxiliary electrode (3), the auxiliary electrode (3) being attached to a position of the third end surface (13) where the inner electrode (2) is exposed and / or a position of the fourth end surface (14) where the inner electrode (2) is exposed, the auxiliary electrode (3) being electrically connected to each of the inner electrodes (2); An external electrode (4), the external electrode (4) being arranged at a position of the first end surface (11) where the internal electrode (2) is exposed or at a position of the second end surface (12) where the internal electrode (2) is exposed, the external electrode (4) being electrically connected to the auxiliary electrode (3) and each of the internal electrodes (2).

2. The conductive structure for a multilayer ceramic capacitor according to claim 1, wherein: The conductive structure for the multilayer ceramic capacitor also includes a protective sheet (5), the protective sheet (5) being bonded to the position of the third end surface (13) where the internal electrode (2) is exposed and / or the position of the fourth end surface (14) where the internal electrode (2) is exposed, and the auxiliary electrode (3) is attached to the bonding end of the protective sheet (5).

3. A multilayer ceramic capacitor, characterized in that: The multilayer ceramic capacitor adopts the conductive structure for ceramic capacitors according to claim 1 or 2; the multilayer ceramic capacitor comprises a ceramic body (1), a first auxiliary electrode (31), a second auxiliary electrode (32), a first external electrode (41) and a second external electrode (42): The ceramic body (1) comprises a plurality of first internal electrodes (21) and a plurality of second internal electrodes (22) which are alternately arranged in a first direction (Z); each of the first internal electrodes (21) is arranged at an interval from the second end surface (12) of the ceramic body (1), and each of the second internal electrodes (22) is arranged at an interval from the first end surface (11) of the ceramic body (1); Each of the first internal electrodes (21) is exposed to the first end surface (11) of the ceramic body (1), and is exposed to the third end surface (13) and / or the fourth end surface (14) of the ceramic body (1); the first auxiliary electrode (31) is provided at the position of the third end surface (13) where the first internal electrode (21) is exposed and / or at the position of the fourth end surface (14) where the first internal electrode (21) is exposed, and the first auxiliary electrode (31) is electrically connected to each of the first internal electrodes (21); the first external electrode (41) is provided on the first end surface (11), and the first external electrode (41) is electrically connected to the first auxiliary electrode (31) and each of the first internal electrodes (21) exposed to the first end surface (11); Each of the second inner electrodes (22) is exposed to the second end surface (12) and is exposed to the third end surface (13) and / or the fourth end surface (14); the third end surface (13) and / or the fourth end surface (14) are provided with the second auxiliary electrode (32), and the second auxiliary electrode (32) is electrically connected to the second inner electrode (22) exposed to the third end surface (13) and / or the fourth end surface (14); the second outer electrode (42) is arranged on the second end surface (12), and the second outer electrode (42) is electrically connected to the second auxiliary electrode (32) and each of the second inner electrodes (22) exposed to the second end surface (12).

4. The multilayer ceramic capacitor according to claim 3, wherein: The first inner electrode (21) is exposed to the third end surface (13) and the fourth end surface (14); the third end surface (13) and the fourth end surface (14) are both provided with the first auxiliary electrodes (31); each of the first auxiliary electrodes (31) is arranged at intervals from each of the second inner electrodes (22); and an end of each of the first auxiliary electrodes (31) extends to the first end surface (11); The second inner electrode (22) is exposed to the third end surface (13) and the fourth end surface (14); the third end surface (13) and the fourth end surface (14) are both provided with the second auxiliary electrodes (32); each of the second auxiliary electrodes (32) is arranged at intervals from each of the first inner electrodes (21); and an end portion of each of the second auxiliary electrodes (32) extends to the second end surface (12).

5. The multilayer ceramic capacitor according to claim 4, characterized in that: The multilayer ceramic capacitor comprises a first protective sheet (51) attached to the third end surface (13) and a second protective sheet (52) attached to the fourth end surface (14); The first auxiliary electrode (31) and the second auxiliary electrode (32) located on the third end surface (13) are attached to the bonding end of the first protective sheet (51) by means of additive manufacturing; The first auxiliary electrode (31) and the second auxiliary electrode (32) located on the fourth end surface (14) are attached to the bonding end of the second protective sheet (52).

6. The multilayer ceramic capacitor according to claim 3, wherein: The first internal electrode (21) is exposed to the third end surface (13), and the first internal electrode (21) is arranged at a distance from the fourth end surface (14), and the first auxiliary electrode (31) is arranged on the third end surface (13); The second inner electrode (22) is exposed to the fourth end surface (14), and the second inner electrode (22) is arranged at a distance from the third end surface (13), and the second auxiliary electrode (32) is arranged on the fourth end surface (14).

7. The multilayer ceramic capacitor according to claim 6, wherein: The multilayer ceramic capacitor comprises a third protective sheet (53) attached to the third end surface (13) and a fourth protective sheet (54) attached to the fourth end surface (14); The first auxiliary electrode (31) is a conductive layer attached to the bonding end of the third protective sheet (53) by additive manufacturing, and the second auxiliary electrode (32) is a conductive layer attached to the bonding end of the fourth protective sheet (54).

8. The multilayer ceramic capacitor according to claim 3, wherein: The thickness of each of the first internal electrodes (21) and the thickness of each of the second internal electrodes (22) are both greater than or equal to 0.5 μm and less than or equal to 1 μm.

9. The multilayer ceramic capacitor according to claim 3, wherein: The thickness of the first auxiliary electrode (31) and the second auxiliary electrode (32) are both greater than or equal to 0.5 μm and less than or equal to 3 μm.

10. A method for manufacturing a multilayer ceramic capacitor according to any one of claims 3 to 9, characterized in that: The following steps are involved: Step S1, preparing a primary ceramic body mother bar (103) and a protection bar (200), wherein the primary ceramic body mother bar (103) is formed with a plurality of ceramic body units (1031) arranged in sequence along a first direction (X), and the protection bar (200) is formed with a plurality of protection sheet units (201) arranged in sequence along the first direction (X); Step S2, pressing the protection strip (200) onto the third end face and the fourth end face of the primary ceramic body mother bar (103) to form a final ceramic body mother bar (104); Step S3, dividing the final ceramic body mother bar (104) into a plurality of green ceramic bodies (400) along the first direction (X); Step S4, sintering the green ceramic body (400) into a finished ceramic body; Step S5, processing a first external electrode (41) and a second external electrode (42) on the first end surface and the second end surface of the finished ceramic body.

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